Global Positioning Systems (“GPS”) enable a device to determine its location on the surface of the Earth. Many systems have been developed that utilize GPS to assist drivers in navigating their vehicles. Before GPS, the driver had a difficult time not only finding a route between their current location and a selected destination, but also in selecting the best route to meet the driver's goals.
One goal some drivers have is to minimize the amount of fuel usage required to travel between the current location and a selected destination. This goal has become even more pronounced with the rising cost of fuel. Finding the street route that will use the minimum fuel usage can be very difficult as it can depend on many factors, including the grade of the streets, the traffic conditions, the number and length of stops in the route, the speed limits of the street route, and the effect of speed on the fuel efficiency of the vehicle. This is further complicated because the exact conditions of the vehicle and the route may not be known. And further, it may be that the driver desires to avoid problems in the route such as dangerous intersections.
U.S. Pat. No. 5,742,922 entitled “Vehicle Navigation System and Method for Selecting a Route According to Fuel Consumption” provides for determining a least fuel consumption route in view of the altitude information of the route, but does not account for the effect of speed on the fuel efficiency of the vehicle and does not account for the usage of fuel for stopping or slowing down to turn.
Accordingly, it would be advantageous to provide methods and apparatus that allow for determining a route having a minimum fuel usage for a vehicle based on the estimated effect of speed on the fuel consumption of the vehicle and estimated speeds for the street route as well as an estimated amount of fuel used based on an estimated number of stops the vehicle will make and an estimated number of times the vehicle will slow down to turn. It would be further advantageous to take into account the driver's preferences for a route.